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A supercapacitor electrode featured with a voltage self-stabilizing capability is demonstrated by growing indium tin oxide (ITO) nanowires on Ni foam. The ITO nanowires with a single crystal structure are prepared by using magnetron sputtering technique, and they can act as an active electrode material. Charging–discharging experiments are performed under different current densities, demonstrating a good rate capability. Using properly designing top and bottom double connection circuits, part of the electrode can be used as a resistance switch. An electrode that can function as a supercapacitor and a resistance switch is fabricated. Detailed characteristics confirm that the device not only exhibits high performance as a supercapacitor but also has good characteristics of resistance switching (RS). The specific capacitance is 956 F/g at the scanning rate of 10 mV/s, and the switching ratio as a bipolar resistance switch is as high as 102. The stabilization time of discharging voltage is nearly doubled longer than that without any RS function, revealing the potential application of our devices, which can be used as a supercapacitor with voltage self-stabilizing.
Laser pulses of 200 ps with extremely high intensities and high energies are sufficient to satisfy the demand of shock ignition, which is an alternative path to ignition in inertial confinement fusion (ICF). This paper reports a type of Brillouin scheme to obtain high-intensity 200-ps laser pulses, where the pulse durations are a challenge for conventional pulsed laser amplification systems. In the amplification process, excited Brillouin acoustic waves fulfill the nonlinear optical effect through which the high energy of a long pump pulse is entirely transferred to a 200-ps laser pulse. This method was introduced and achieved within the SG-III prototype system in China. Compared favorably with the intensity of
in existing ICF laser drivers, a 6.96-
pulse with a width of 170 ps was obtained in our experiment. The practical scalability of the results to larger ICF laser drivers is discussed.
Shot-peened CM400 maraging steel was used to study the mechanism of enhanced notch fatigue properties of ultra-high strength materials. After shot peening, the specimen surface became rougher, but the transversal machining traces were reduced. The yield strength was slightly improved while the ultimate tensile strength and hardness maintained constant; as a result, the fatigue limit was promoted by about 1.5 times. The nucleated sites of the fatigue fracture were partly changed from the surface to subsurface/interior of the specimen. To further analyze the influencing factors of fatigue properties, the fatigue damage process may be resolved to two aspects: (a) fatigue damage rate affected by shear deformation and (b) fatigue damage tolerance controlled by the dilatation fracture process. Considering the stress state near the notch tip, the hydrostatic stress and maximum shear stress are considered for better understanding these two aspects. It is observed that the fatigue damage tolerance increased while the fatigue damage rate decreased after shot peening. Therefore, the notch fatigue properties of CM400 maraging steels can effectively be improved.
Polystyrene spheres were found to be an effective assisted material in the growth of indium-tin-oxide (ITO) nanowire networks, bearing low temperature, high purity, and good control of size. The temperature and time of growth were studied to achieve ITO nanowire networks with high transmission and low resistivity. When prepared by PS spheres of 670 nm dia. for 15 min at 300 °C, the transmittance is above 90% after the wave length of 400 nm, and the sheet resistance is ∼200 Ω/□. Polystyrene-assisted ITO nanowires showed the high degree of crystallinity with lattice fringes, and well coincided cubic phase of In2O3. The density of ITO nanowire networks were controlled by polystyrene spheres and the residual polystyrene was removed by thermal annealing. ITO nanowire networks open new opportunities for optoelectronic devices needing special morphology for the improvement of light extraction efficiency, and as a new type of conductive film, which have an even broad application arena.
An effective multiplex real-time polymerase chain reaction (PCR) assay for the simultaneous detection of three major pathogens, Nosema bombycis Nägeli (Microsporidia: Nosematidae), Bombyx mori nucleopolyhedrovirus (Baculoviridae: genus Alphabaculovirus) (NPV), and Bombyx mori densovirus (Parvoviridae: genus Iteravirus) (DNV), in silkworms (Bombyx mori (Linnaeus); Lepidoptera: Bombycidae) was developed in this study. Polymerase chain reaction and real-time PCR tests and basic local alignment search tool searches revealed that the primers and probes used in this study had high specificities for their target species. The ability of each primer/probe set to detect pure pathogen DNA was determined using a plasmid dilution panel, in which under optimal conditions the multiplex real-time PCR assay showed high efficiency in the detection of three mixed target plasmids with a detection limit of 8.5×103 copies for N. bombycis and Bombyx mori NPV (BmNPV) and 8.5×104 copies for Bombyx mori DNV (BmDNV). When the ability to detect these three pathogens was examined in artificially inoculated silkworms, our method presented a number of advantages over traditional microscopy, including specificity, sensitivity, and high-throughput capabilities. Under the optimal volume ratio for the three primer/probe sets (3:2:2=N. bombycis:BmNPV:BmDNV), the multiplex real-time PCR assay showed early detection of BmNPV and BmDNV by day 1 post inoculation using DNA templates of the three pathogens in various combinations from individually infected silkworms; the early detection of N. bombycis was possible by day 3 post inoculation using the DNA isolated from the midgut of N. bombycis-infected silkworms.
Phase stability, elastic, and thermodynamic properties of (Co,Ni)3(Al,Mo,Nb) with the L12 structure have been investigated by first-principles calculations. Calculated phonon density of states show that (Co,Ni)3(Al,Mo,Nb) is dynamically stable, and calculated elastic constants indicate that (Co,Ni)3(Al,Mo,Nb) possesses intrinsic ductility. Young’s and shear moduli of the simulated polycrystalline (Co,Ni)3(Al,Mo,Nb) phase are calculated using the Voigt–Reuss–Hill approach and are found to be smaller than those of Co3(Al,W). Calculated electronic density of states depicts covalent-like bonding existing in (Co,Ni)3(Al,Mo,Nb). Temperature-dependent thermodynamic properties of (Co,Ni)3(Al,Mo,Nb) can be described satisfactorily using the Debye–Grüneisen approach, including heat capacity, entropy, enthalpy, and linear thermal expansion coefficient. Predicted heat capacity, entropy, and linear thermal expansion coefficient of (Co,Ni)3(Al,Mo,Nb) show significant change as a function of temperature. Furthermore the obtained data can be used in the modeling of thermodynamic and mechanical properties of Co-based alloys to enable the design of high temperature alloys.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
Many lacustrine chronology records suffer from radiocarbon reservoir effects. A continuous, accurate varve chronology, in conjunction with accelerator mass spectrometry (AMS) 14C dating, was used to determine the age of lacustrine sediment and to quantify the past 14C reservoir effect in Sugan Lake (China). Reservoir age varied from 4340 to 2590 yr due to 14C-depleted water in the late Holocene. However, during the Little Ice Age (LIA), 14C reservoir age was relatively stable. According to this study, 14C reservoir age in the late Holocene may be driven by hydrological and climatic changes of this period. Therefore, special caution should be paid to the correction of the 14C reservoir effect by a unique 14C reservoir age in paleoclimatic and paleolimnological study of northwest China.
The surface microstructure of shot peened (TiB + TiC)/Ti–6Al–4V is investigated using Rietveld whole pattern fitting method. The domain size and microstrain of them are obtained. By comparing the calculated results between them, it can be found that the microstructure variations of Ti–6Al–4V are more severe than those of (TiB + TiC)/Ti–6Al–4V, which is due to the effect of reinforcements' resistance to the deformation of the surface layer. The distribution of average domain size and microstrain of (TiB + TiC)/Ti–6Al–4V at varying depths are calculated, and the results are discussed in detail. Moreover, the probability distribution of the domain size at different depths is obtained using the lognormal distribution model. Based on the discussion, the results obtained from Rietveld whole pattern fitting method agree with the results calculated using the Voigt method, which reveals that the Rietveld method is an effective method of characterizing the surface microstructure of titanium matrix composites after shot peening treatments.
We investigated the time lags and the evolution of the cross spectrua of Z source GX 5-1, observed by Rossi X-ray Timing Explorer (RXTE), when it is in the horizontal branch oscillations. We showed that the time lags of 3 horizontal branch oscillations are related to the position on the hardness intensity diagram. 3 QPOs were shown to be of the hard time lags. But on the cross spectra, one is in a “dip”, one in a “bump”, another has not that chracteristic. The time lags of two of the QPOs decrease with QPO's frequency, and one has a trend increasing with its freuqency. In the normal branch, we found that there is no significant time lags in the present observational data.
Psychiatric disorders such as schizophrenia and major depressive disorder
(MDD) are likely to be caused by multiple susceptibility genes, each with
small effects in increasing the risk of illness. Identifying DNA variants
associated with schizophrenia and MDD is a crucial step in understanding
the pathophysiology of these disorders.
To investigate whether the SP4 gene plays a significant
role in schizophrenia or MDD in the Han Chinese population.
We focused on nine single nucleotide polymorphisms (SNPs) harbouring the
SP4 gene and carried out case–control studies in 1235
patients with schizophrenia, 1045 patients with MDD and 1235 healthy
controls recruited from the Han Chinese population.
We found that rs40245 was significantly associated with schizophrenia in
both allele and genotype distributions (Pallele = 0.0005, Pallele = 0.004 after Bonferroni correction; Pgenotype = 0.0023, Pgenotype = 0.0184 after Bonferroni correction). The rs6461563
SNP was significantly associated with schizophrenia in the allele
distributions (Pallele = 0.0033, Pallele = 0.0264 after Bonferroni correction).
Our results suggest that common risk factors in the SP4
gene are associated with schizophrenia, although not with MDD, in the Han
This paper investigates the trajectory tracking of a Stewart platform, which is a typical multi-input multi-output nonlinear system, with unmodeled dynamics, parameter uncertainties, friction, and unpredictable actuator faults. An adaptive vector sliding mode fault-tolerant control law is derived to ensure the system is insensitive to uncertainties and drive the state variable errors of the closed-loop system to converge to the origin. Moreover, novel adaptive laws are proposed to update the upper boundary of uncertainty according to the actual system state, which greatly reduces the chattering of sliding mode control. Furthermore, velocity signals are estimated by introducing a simple nonlinear observer, resulting in the proposed controller requiring position measurements only. Finally, numerical simulations illustrate the effectiveness of the proposed control scheme.
This paper describes an MHD simulation of an observed Sigmoid in AR 11283 from its formation to eruption. The Non-linear Force Free MHD model (Jiang and Feng, 2012) and the data-driven active region evolution model (Wu et al., 2006; Jiang et al. 2013) together with the SDO/HMI magnetograms are used. We show the successful simulation results of the eruption of a flux-rope structure.
Industry-generated trans-fatty acids (TFA) are detrimental to risk of CHD, but ruminant-originated TFA have been reported as neutral or equivocal. Therefore, the total TFA amount should not be the only factor considered when measuring the effects of TFA. In the present study, we addressed whether a version of the TFA index that unifies the effects of different TFA isomers into one equation could be used to reflect CHD risk probability (RP). The present cross-sectional study involved 2713 individuals divided into four groups that represented different pathological severities and potential risks of CHD: acute coronary syndrome (ACS, n 581); chronic coronary artery disease (CCAD, n 631); high-risk population (HRP, n 659); healthy volunteers (HV, n 842). A 10-year CHD RP was calculated. Meanwhile, the equation of the TFA index was derived using five TFA isomers (trans-16 : 1n-7, trans-16 : 1n-9, trans-18 : 1n-7, trans-18 : 1n-9 and trans-18 : 2n-6n-9), which were detected in the whole blood, serum and erythrocyte membranes of each subject. The TFA index and the 10-year CHD RP were compared by linear models. It was shown that only in the erythrocyte membrane, the TFA isomers were significantly different between the groups. In the ACS group, industry-generated TFA (trans-16 : 1n-9, trans-18 : 1n-9 and trans-18 : 2n-6n-9) were the highest, whereas ruminant-originated TFA (trans-16 : 1n-7 and trans-18 : 1n-7), which manifested an inverse relationship with CHD, were the lowest, and vice versa in the HV group. The TFA index decreased progressively from 7·12 to 5·06, 3·11 and 1·92 in the ACS, CCAD, HRP and HV groups, respectively. The erythrocyte membrane TFA index was positively associated with the 10-year CHD RP (R2 0·9981) and manifested a strong linear correlation, which might reflect the true pathological severity of CHD.
Williams syndrome is caused by a gene deletion of chromosome 7. A majority of the cases are sporadic with typical facial appearance, cardiac anomalies, and mental retardation. We report a rare case of Williams syndrome associated with supravalvular aortic stenosis, subvalvular aortic membrane, mitral regurgitation, aortic coarctation, and patent ductus arteriosus. The patient had undergone a single-stage surgical repair with satisfactory results at 5 months of follow-up.
The spatially developing compressible plane mixing layer with a convective Mach number of 0.7 is investigated by direct numerical simulation. A pair of equal and opposite oblique instability waves is introduced to perturb the mixing layer at the inlet. The full evolution process of instability, including formation of -vortices and hairpin vortices, breakdown of large structures and establishment of self-similar turbulence, is presented clearly in the simulation. In the transition process, the flow fields are populated sequentially by -vortices, hairpin vortices and ‘flower’ structures. This is the first direct evidence showing the dominance of these structures in the spatially developing mixing layer. Hairpin vortices are found to play an important role in the breakdown of the flow. The legs of hairpin vortices first evolve into sheaths with intense vorticity then break up into small slender vortices. The later flower structures are produced by the instability of the heads of the hairpin vortices. They prevail for a long distance in the mixing layer until the flow starts to settle down into its self-similar state. The preponderance of slender inclined streamwise vortices is observed in the transversal middle zone of the transition region after the breakup of the hairpin legs. This predominance of streamwise vortices also persists in the self-similar turbulent region, though the vortices there are found to be relatively very weak. The evolution of both the mean streamwise velocity profile and the Reynolds stresses is found to have close connection to the behaviour of the large vortex structures. High growth rates of the momentum and vorticity thicknesses are observed in the transition region of the flow. The growth rates in the self-similar turbulence region decay to a value that agrees well with previous experimental and numerical studies. Shocklets occur in the simulation, and their formation mechanisms are elaborated and categorized. This is the first three-dimensional simulation that captures shocklets at this low convective Mach number.
The current study explored the effects of treadmill exercise intensity on functional recovery and hippocampal phospho-NR2B (p-NR2B) expression in cerebral ischemic rats, induced by permanent middle cerebral artery occlusion (MCAO) surgery.
Adult male Sprague-Dawley rats were randomly divided into four groups, including sham, no exercise (NE), low intensity training (LIT, v = 15 m/min), and moderate intensity training groups (MIT, v = 20 m/min). At different time points, the hippocampal expressions of p-NR2B and total NR2B were examined. In addition, neurological deficit score (NDS), body weight, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to evaluate brain infarct volume as assessments of post-stroke functional recovery. In order to investigate the effect of exercise on survival, the mortality rate was also recorded.
The results showed that treadmill exercise significantly decreased hippocampal expression of p-NR2B but didn't change the total NR2B, compared to the NE group on the 3rd, 7th, and 14th days following MCAO surgery. The effect on changes in p-NR2B levels, body weight, and brain infarct volume were more significant in the LIT compared to the MIT group.
Discussion and Conclusion:
The current findings demonstrate that physical exercise can produce neuroprotective effects, in part by down-regulating p-NR2B expression. Furthermore, the appropriate intensity of physical exercise is critical for post-stroke rehabilitation.
In this work, a novel core–shell structured hybrid graphene oxide-encapsulated silica (GO–SiO2) was first fabricated via an electrostatic assembly between negatively charged graphene oxide (GO) sheets and positively charged sub-micro-sized silica. Then, the new kind of hybrid filler was used for the in situ preparation of poly(ethylene terephthalate) (PET)/GO–SiO2 composites. The microstructure and mechanical properties of the prepared composites were analyzed by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, dynamic mechanical analysis measurements, and tensile test. It was found that GO could be covalently assembled onto the subsized silica surface via its plenty of functional groups that can also provide strong interaction with the PET. As a result, a uniform dispersion of GO–SiO2 hybrids and enhanced interfacial adhesion as well as improved mechanical property have been evidenced. The new concept of using GO as a potent inorganic fillers surface modifier may broaden the use of GO and provides a new idea for the design and fabrication of advanced polymer composites.